Re: [PATCH v6] page_alloc: allow migration of smaller hugepages during contig_alloc

[Gregory Price]

On Fri, Dec 19, 2025 at 12:08:00AM +0000, Wei Yang wrote:
> >+
> >+			page = compound_head(page);
> >+			order = compound_order(page);
> 
> The order is get from head page.
> 
> >+			if ((order >= MAX_FOLIO_ORDER) ||
> >+			    (nr_pages <= (1 << order)))
> >+				return false;
> >+
> >+			/* No need to check the pfns for this page */
> >+			i += (1 << order) - 1;
> 
> So this advance should based on "head page" instead of original page, right?
>

hm, I think the thought here was that since we're moving forward from
start of an aligned chunk, we'd never hit a non-head page - but this
may not be true.  

Will think about this for a bit.

~Gregory